305 citations · 1.2k across the 33 of their papers we have counts for
33 papers
Spin-Orbit Geometry of AU Mic b and c from Back-to-Back Transits Observed Contemporaneously with Magellan PFS, LCOGT, and CHEOPS
Zitao Lin, Gyula M. Szabó, Krzysztof Sz. Zieliński +37
Young planets offer a unique window into the early stages of planetary evolution. AU Mic is one of the nearest (9.8 pc) pre-main sequence stars (~20 Myr), hosting two transiting Ne…
Gas-depleted planet formation occurred in the four-planet system around the red dwarf LHS 1903
Thomas G. Wilson, Anna M. Simpson, Andrew Collier Cameron +173
Small exoplanet radii show two populations, referred to as super-Earths and sub-Neptunes, separated by a gap known as the radius valley. This may be produced by the removal of atmo…
Atmospheric characterization of HIP 67522 b with VLT/CRIRES+. VLT/CRIRES+ suggests a heavier planet and hints at deuterium fractionation
A. Lavail, F. Debras, B. Klein +9
Young transiting exoplanets provide unique opportunities to probe planetary atmospheres during the critical early phases of evolution. HIP 67522 b, a 17 Myr old hot Jupiter with an…
Mass estimates of the young TOI-451 transiting planets: Multidimensional Gaussian Process on stellar spectroscopic and photometric signals
Oscar Barragán, Manuel Mallorquín, Jorge Fernández-Fernández +30
The young TOI-451 planetary system, aged 125 Myr, provides a unique opportunity to test theories of planetary internal structures and atmospheric mass loss through examination of i…
Transformational astrophysics and exoplanet science with Habitable Worlds Observatory's High Resolution Imager
Vincent Van Eylen, Richard Massey, Saeeda Awan +167
Habitable Worlds Observatory (HWO) will be NASA's flagship space telescope of the 2040s, designed to search for life on other planets and to transform broad areas of astrophysics.…
A Decade of Solar High-Fidelity Spectroscopy and Precise Radial Velocities from HARPS-N
X. Dumusque, K. Al Moulla, M. Cretignier +53
We recently released 10 years of HARPS-N solar telescope and the goal of this manuscript is to present the different optimisations made to the data reduction, to describe data cura…
ATREIDES I. Embarking on a trek across the exo-Neptunian landscape with the TOI-421 system
V. Bourrier, M. Steiner, A. Castro-González +75
The distribution of close-in exoplanets is shaped by the interplay between atmospheric and dynamical processes. The Neptunian Desert, Ridge, and Savanna illustrate the sensitivity…
Granulation on a quiet K dwarf: HD 166620 I. Spectral signatures as a function of line-formation temperature
Ancy Anna John, Khaled Al Moulla, Niamh K. O'Sullivan +14
As Radial velocity (RV) spectrographs reach unprecedented precision and stability below 1 m/s, the challenge of granulation in the context of exoplanet detection has intensified. D…
Using Doppler Imaging to model stellar activity and search for planets around Sun-like stars
Baptiste Klein, Suzanne Aigrain, Michael Cretignier +9
Doppler Imaging (DI) is a well-established technique to map a physical field at a stellar surface from a time series of high-resolution spectra. In this proof-of-concept study, we…
Measuring the Suns radial velocity variability due to supergranulation over a magnetic cycle
Niamh K. O'Sullivan, Suzanne Aigrain, Michael Cretignier +9
In recent years supergranulation has emerged as one of the biggest challenges for the detection of Earth-twins in radial velocity planet searches. We used eight years of Sun-as-a-s…
A possible misaligned orbit for the young planet AU Mic c
H. Yu, Z. Garai, M. Cretignier +98
The AU Microscopii planetary system is only 24 Myr old, and its geometry may provide clues about the early dynamical history of planetary systems. Here, we present the first measur…
Stellar surface information from the Ca II H&K lines -- II. Defining better activity proxies
M. Cretignier, N. C. Hara, A. G. M. Pietrow +6
In our former paper I, we showed on the Sun that different active regions possess unique intensity profiles on the Ca II H & K lines. We now extend the analysis by showing how thos…
A Gaussian process model for stellar activity in 2-D line profile time-series
Haochuan Yu, Suzanne Aigrain, Baptiste Klein +3
Stellar active regions like spots and faculae can distort the shapes of spectral lines, inducing variations in the radial velocities that are often orders of magnitude larger than…
Revisiting the dynamical masses of the transiting planets in the young AU Mic system: Potential AU Mic b inflation at 20 Myr
M. Mallorquín, V. J. S. Béjar, N. Lodieu +26
Understanding planet formation is important in the context of the origin of planetary systems in general and of the Solar System in particular, as well as to predict the likelihood…
Measuring stellar surface rotation and activity with the PLATO mission -- I. Strategy and application to simulated light curves
S. N. Breton, A. F Lanza, S. Messina +20
The Planetary Transits and Oscillations of stars mission (PLATO) will allow us to measure surface rotation and monitor photometric activity of tens of thousands of main sequence so…
Investigating stellar activity through eight years of Sun-as-a-star observations
Baptiste Klein, Suzanne Aigrain, Michael Cretignier +11
Stellar magnetic activity induces both distortions and Doppler-shifts in the absorption line profiles of Sun-like stars. Those effects produce apparent radial velocity (RV) signals…
Planet Hunters TESS V: a planetary system around a binary star, including a mini-Neptune in the habitable zone
Nora L. Eisner, Samuel K. Grunblatt, Oscar Barragán +61
We report on the discovery and validation of a transiting long-period mini-Neptune orbiting a bright (V = 9.0 mag) G dwarf (TOI 4633; R = 1.05 RSun, M = 1.10 MSun). The planet was…
Modelling stochastic and quasi-periodic behaviour in stellar time-series: Gaussian process regression versus power-spectrum fitting
Niamh K. O'Sullivan, Suzanne Aigrain
As the hunt for an Earth-like exoplanets has intensified in recent years, so has the effort to characterise and model the stellar signals that can hide or mimic small planetary sig…
REPUBLIC: A variability-preserving systematic-correction algorithm for PLATO's multi-camera light curves
Oscar Barragán, Suzanne Aigrain, James McCormac
Space-based photometry missions produce exquisite light curves that contain a wealth of stellar variability on a wide range of timescales. Light curves also typically contain signi…
TOI-837b is a Young Saturn-sized Exoplanet with a Massive 70 Core
Oscar Barragán, Haochuan Yu, Alix Violet Freckelton +10
We present an exhaustive photometric and spectroscopic analysis of TOI-837, a F9/G0 35 Myr young star, hosting a transiting exoplanet, TOI-837b, with an orbital period of 8.32d. Ut…
Modelling stellar variability in archival HARPS data: I -- Rotation and activity properties with multi-dimensional Gaussian Processes
Haochuan Yu, Suzanne Aigrain, Baptiste Klein +4
Although instruments for measuring the radial velocities (RVs) of stars now routinely reach sub-meter per second accuracy, the detection of low-mass planets is still very challengi…
Stellar surface information from the Ca II H&K lines I. Intensity profiles of the solar activity components
M. Cretignier, A. G. M. Pietrow, S. Aigrain
The detection of Earth-like planets with the radial-velocity method is currently limited by the presence of stellar activity signatures. On rotational timescales, spots and plages…
HD152843 b & c: the masses and orbital periods of a sub-Neptune and a super-puff Neptune
B. A. Nicholson, S. Aigrain, N. L. Eisner +24
We present the characterisation of the two transiting planets around HD 152843 (TOI 2319, TIC 349488688) using an intensive campaign of HARPS-N radial velocities, and two sectors o…
Separating planetary reflex Doppler shifts from stellar variability in the wavelength domain
A. Collier Cameron, E. B. Ford, S. Shahaf +28
Stellar magnetic activity produces time-varying distortions in the photospheric line profiles of solar-type stars. These lead to systematic errors in high-precision radial-velocity…